C-CEX withdraw problem need help

I withdrawed 10000 XBY to the address(BQmgx9JpvJ7K8CMFjavCa4a5Vy3f8jaxEb) from C-CEX on about 2018-01-01 when the withdraw service is on maintenance. I just remebered it and checked my wallet. It has been reduced from my C-CEX wallet and i haven’t got it on the above address. I also can’t find it on the withdraw history. But You can check the XBY buy and sell history. I bought 754804.3132 and sell 113358.908 XBY from 2017-12-31 when my XBY amount is 0. Now I have 631445 XBY.
754804 -113358–631445=10000.
I cannot get touch with C-CEX. Please help me. My C-CEX ID is rushui223.